The present invention relates to a release preventing device for a fishing reel, and more particularly, to a release preventing device provided with a one-way clutch that allows a rotating body, such as the spool of a double-bearing type fishing reel and a rotor of a spinning reel, to rotate in one direction but restricts rotation of that rotating body in the other direction by means of a wedge effect from roller members.
In a release preventing device for a fishing reel as described in Japanese Patent Application Kokai (OPI) No. SHO-48-90882 and Japanese Utility Model Application Kokai (OPI) No. SHO-64-38964, an inner race and an outer race of a one-way clutch are attached, respectively, to a fixed member of a reel body and to a rotatable part. The rotatable part is for example, a handle rotatably supported by the reel body and a rotatable part drivingly connected to a motor. The wedge effect from roller members provided in a guide groove between the inner and outer races allows rotation of the rotating unit in one direction (the normal direction) but restricts rotation in the other (the reverse direction).
A release preventing device for a fishing reel as described in Japanese Patent Application Kokai (OPI) No. SHO-54-141285 is provided with bearings between a shaft sleeve portion of a rotor rotatably supported in the reel body, and a front portion of the reel body. The bearings are provided for rotation in only the normal direction, while rotation in the reverse direction is restricted according to a wedge effect from roller members. A restricting plate rotatably provided on the front side of the bearings contains locking pieces that protrude into a guide groove retaining the roller members. When the restricting plate is rotated by an operating rod supported on the reel body, the roller members are changed to a non-wedge position, allowing the rotating body to rotate in the reverse direction.
A unit assembly for a release preventing device is described in Japanese Patent Application Kokai (OPI) No. HEI-6-58348. In this unit assembly, an annular holder is provided for restricting front-and-rear movement of the roller members described in Japanese Patent Application Kokai (OPI) No. SHO-54-141285. Further, an external frame (outer race) for restricting radially outward movement of the roller members is fitted tightly around the outside of the annular holder.
Another unit assembly for a release preventing device is described in Japanese Patent Application Kokai (OPI) No. HEI-6-225673. In this unit assembly, an external frame (outer race) for restricting radially outward movement of the roller members is rotatably fitted around the outside of the annular holder described in Japanese Patent Application Kokai (OPI) No. HEI-6-58348. In addition, the roller members are changed to a non-wedge position when the annular holder is rotated by an operating rod supported on the reel body.
Japanese Patent Application Kokai (OPI) No. HEI-7-246047 discloses a release preventing device in which an annular holder is integrally provided with the reel body in a concentrical arrangement with a rotatable part such as a shaft sleeve portion of the rotor and is positioned radially outwardly of the shaft sleeve portion. The annular holder retains roller members which are in contact with the rotatable part for restricting rotation of the rotatable part in one direction. Further, an external frame (outer race) is rotatably disposed around the annular holder for preventing radially outward displacement of the roller members. An operating rod supported by the reel body rotates the external frame so as to switch the roller members into non-wedge position.
However, in the release preventing devices described in these publications rotation of the rotatable part such as the shaft sleeve of the rotor is prevented by radially inward movement of the roller members, while radially outward movement of the roller members is restrained by the external frame or the outer race. For this reason, restriction of rotation is performed at a position as close to the rotational center of the rotating body as possible. Hence, not only is it difficult to create sufficient restrictive force, but a large rotational force may widen the guide groove due to the wedge effect of the roller members, inviting deformation or damage to the outer race.
In a technique described in Japanese Utility Model Application Kokai (OPI) No. HEI-4-77774 for improving the rotational restrictive strength and the durability of a release preventing device, the device is provided with bearings on an inner peripheral surface of a hollow cylindrical portion of a rotor. The bearings are provided for rotation of a rotatable part in only the normal direction, while rotation in the reverse direction is restricted according to a wedge effect from roller members. When pawls are disengaged by an operating rod supported on the reel body from depressions provided on the inner periphery of the internal frame (inner race), the rotatable part can rotate in the reverse direction. An external frame (outer race) is provided on the inner peripheral surface of the hollow cylindrical portion of the rotor for restricting radially outward movement of the roller members.
According to the bearings described in Japanese Utility Model Application Kokai (OPI) No. HEI-4-77774, rotation of the internal frame is restricted by radially inward movement of the roller members, while radially outward movement of the roller members is restrained by the external frame or the outer race. This configuration incurs the same problems described above.
Further, in the release preventing device of Japanese Utility Model Application Kokai (OPI) No. HEI-4-77774, since permission and prevention of the reversal rotation of the internal frame is performed by engagement and disengagement of the pawls with and from the depressions formed on the inner periphery of an internal frame, the operating speed degrades in comparison to a configuration allowing rotation in the reverse direction when the roller members are moved to a non-wedge position. Also, since an external frame (outer race) for restricting radially outward movement of the roller members is provided on the inner peripheral surface of the hollow cylindrical portion of the rotor, the roller members may be separated from the internal frame (inner race) due to centrifugal force if the rotor is rotated at high speed. As a result, quick and reliable release prevention cannot be achieved.
In order to avoid this separation problem, biasing means can be provided to urge the roller members radially inwardly, i.e., in a wedge effecting direction to provide such reliable release prevention. However, the strengthened urging force will affect smooth normal rotation of the internal frame because the roller members are forcibly urged onto the internal frame.
As information, U.S. Pat. No. 4,185,723 discloses an automatic four-wheel drive transfer case having a friction clutch. U.S. Pat. No. 4,415,072 discloses a one-way clutch formed between an inner race and an outer race. U.S. Pat. No. 4,230,211 discloses a free wheel hub apparatus for vehicles. U.S. Pat. No. 5,443,147 discloses a rotationally dependent free-wheeling coupling. Japanese patent application Kokai (OPI) No. SHO 56-143823 and Japanese patent publication No. SHO 38-25312 disclose a one way clutch. Japanese patent application Kokai (OPI) No. SHO52-137552 discloses an intermittent rotation clutch.